connect_pair
function (which will
fail with an operation_not_supported error).
ip::basic_resolver
.
experimental::as_single
completion token adapter.
The as_single
completion token adapter can be used to specify
that the completion handler arguments should be combined into a single
argument. For completion signatures with a single parameter, the argument
is passed through as-is. For signatures with two or more parameters, the
arguments are combined into a tuple. The as_single
adapter
may be used in conjunction with use_awaitable
and structured
bindings as follows:auto [e, n] = co_await socket.async_read_some( asio::buffer(data), as_single(use_awaitable));
using default_token = as_single_t<use_awaitable_t<>>; using tcp_socket = default_token::as_default_on_t<tcp::socket>; // ... awaitable<void> do_read(tcp_socket socket) { // ... auto [e, n] = co_await socket.async_read_some(asio::buffer(data)); // ... }
MSG_NOSIGNAL
on more platforms by using
_POSIX_VERSION
to detect whether it is supported.
executor
concept to test for a const-qualified
execute()
.
any_executor
support for builds without RTTI support.
thread_pool
unit test to work without RTTI support.
asio::query
.
push/pop_options.hpp
includes.
select
reactor is used on Windows.
any_executor
comparisons
and conversion.
strand<>
adaptation of Networking TS executors
when targeting older C++ versions or less conformant compilers.
basic_socket_acceptor
move constructor as noexcept
.
gcc
10's coroutine
support.
windows::overlapped_ptr
.
execution::receiver_of
concept.
execution::executor
,
execution::operation_state
,execution::sender
,
execution::receiver
, execution::receiver_of
,
and execution::scheduler
concepts and the corresponding traits.
These now test first for well-formed CPO expressions (or, in the case of
senders, a specialised sender_traits
template) and, if not
valid, short-circuit the remainder of the evaluation. This helps prevent
recursive template instantiations that can occur in some contexts.
strand
template's constructor, to
prevent template instantiation recursion.
execution::any_executor
template's
converting constructors, as per the specification.
execution::sender_traits
specialisation and
connect()
member function to the thread_pool
executor, as per the specification.
execution::blocking_t::always_t::is_preferable
to
be false as per the specification.
shape_type
and index_type
to thread_pool
executors, as per the specification.
execution::is_executor
)
work with void
.
async_compose
support for standard executors.
any_io_executor
in asio/ts/netfwd.hpp
.
use_future
compatibility with older compilers.
gcc
.
clang-cl
on Windows.
io_context
executors, thread_pool
executors,
system_executor
, and strand<>
.
io_context::executor_type
, thread_pool::executor_type
,
system_executor
, and strand
executors now
meet the requirements for the proposed standard executors. These
classes also continue to meet the existing requirements for the Networking
TS model of executors.
dispatch
, post
, defer
, get_associated_executor
,
bind_executor
, make_work_guard
, spawn
,
co_spawn
, async_compose
, use_future
,
etc., can interoperate with both new proposed standard executors,
and with existing Networking TS executors. The implementation determines
at compile time which model a particular executor meets; the proposed
standard executor model is used in preference if both are detected.
any_io_executor
type alias has been introduced as
the new default runtime-polymorphic executor for all I/O objects.
This type alias points to the execution::any_executor<>
template with a set of supportable properties specified for use with
I/O. This change may break existing code that directly uses the old
polymorphic wrapper, executor
. If required for backward
compatibility, ASIO_USE_TS_EXECUTOR_AS_DEFAULT
can be
defined, which changes the any_io_executor
type alias
to instead point to the executor
polymorphic wrapper.
ASIO_NO_TS_EXECUTORS
.
basic_waitable_timer
.
This enables move construction and assignment between different timer types,
provided the executor types are convertible. For example:basic_waitable_timer< clock_type, traits_type, io_context::executor_type > timer1(my_io_context); basic_waitable_timer< clock_type, traits_type, any_io_executor // polymorphic wrapper > timer2(std::move(timer1));
gcc
10.
co_spawn
that launch an awaitable. This
change allows us to write:co_spawn(executor, echo(std::move(socket)), detached);
co_spawn(executor, [socket = std::move(socket)]() mutable { return echo(std::move(socket)); }, detached);
use_awaitable_t
's default
executor adapter, to enable conversion between executor types.
detached_t
as a default completion
token, by adding members as_default_on()
and as_default_on_t<>
.
ssl::stream<>
.
ssl::stream<>
write operations to linearise
gather-write buffer sequences.
asio_handler_invoke
hook. This hook was deprecated with the introduction of the Networking
TS trait associated_executor
and function get_associated_executor()
.
Compiling an application with ASIO_NO_DEPRECATED
will now
trigger a compile error if any handler implements the asio_handler_invoke
hook.
asio_handler_allocate
and asio_handle_deallocate
hooks. These hooks were deprecated
with the introduction of the Networking TS trait associated_allocator
and function get_associated_allocator()
. Compiling an application
with ASIO_NO_DEPRECATED
will now trigger a compile error if
any handler implements the asio_handler_allocate
or asio_handler_deallocate
hooks.
recv
rather
than recvmsg
, send
rather than sendmsg
,
read
rather than readv
, and write
rather than writev
.
executor
.
errno
and error codes when on an
error path.
io_context::exeutor_type
) is detected.
ASIO_HANDLER_LOCATION((file_name,
line, function_name))
macro may be used to inform the handler tracking
mechanism of a source location. This macro declares an object that is placed
on the stack. Then, when an asynchronous operation is launched with location
information, it outputs lines using the <action>
n^m
, prior to the n*m
line that signifies
the beginning of the asynchronous operation. For example:
@asio|1589423304.861944|>7|ec=system:0,bytes_transferred=5 @asio|1589423304.861952|7^8|in 'async_write' (./../../../include/asio/impl/write.hpp:330) @asio|1589423304.861952|7^8|called from 'do_write' (handler_tracking/async_tcp_echo_server.cpp:62) @asio|1589423304.861952|7^8|called from 'operator()' (handler_tracking/async_tcp_echo_server.cpp:51) @asio|1589423304.861952|7*8|socket@0x7ff61c008230.async_send @asio|1589423304.861975|.8|non_blocking_send,ec=system:0,bytes_transferred=5 @asio|1589423304.861980|<7|
std::source_location
or std::experimental::source_location
are available, the use_awaitable_t
token (when default-constructed
or used as a default completion token) will also cause handler tracking
to output a source location for each newly created asynchronous operation.
A use_awaitable_t
object may also be explicitly constructed
with location information.
handlerviz.pl
tool.
handlerlive.pl
tool, which processes handler
tracking output to produce a list of "live" handlers. Live handlers
are those that are associated with pending asynchronous operations, as
well as handlers that are currently executing. For example:
cat output.txt | perl handlerlive.plor:
perl handerlive.pl < output.txtor:
perl handlerlive.pl output.txt
handlertree.pl
tool, which filters handler
tracking output to include only those events in the tree that produced
the nominated handlers. For example, to filter the output to include only
the events associated with handlers 123
, 456
,
and their predecessors:
cat output.txt | perl handlertree.pl 123 456or:
perl handlertree.pl 123 456 < output.txt
cat output.txt | \ perl handlertree.pl `perl handlerlive.pl output.txt` | \ perl handlerviz.pl | \ dot -Tsvg > output.svg
async_compose
to work with copyable handlers when passed
by lvalue.
co_spawn
.
Executor
base class from the executor_binder
implementation.
noexcept
.
ssl::host_name_verification
class, which is a drop-in
replacement for ssl::rfc2818_verification
. The ssl::rfc2818_verification
class has been marked as deprecated. As a consequence of this change, SSL
support now depends on functions that were introduced in OpenSSL 1.0.2.
ssl::context
constructor to take ownership of a native
handle.
gcc
to use
__cplusplus
macro.
strand<>
converting constructors and assignment
operators.
async_read
overloads.
ssl::context
class to propagate non-EOF errors
from the add_certificate_authority
function.
thread_pool
destructor hang that
occurred when the pool had an associated I/O object.
select
reactor to recreate the "self
pipe trick" sockets on error. This addresses an issue on some versions
of Windows, where these sockets are discconected after a system sleep.
priority_scheduler
example to demonstrate calls
to shutdown()
and destroy()
.
use_awaitable_t::as_default_on
function.
boost::placeholders
namespace.
async_compose
implementation
due to incorrect overload selection.
async_initiate
helper function to automatically
deduce its return type. This is enabled for C++11 or later.
return_type
.
async_initiate
.
completion_signature<T>
: Checks if T
is a signature of the form R(Args...)
.
completion_handler_for<T, Signature>
: Checks if
T
is usable as a completion handler with the specified
signature.
completion_token_for<T, Signature>
: Checks if
T
is a completion token that can be used with async_initiate
and the specified signature.
(BOOST_)ASIO_COMPLETION_SIGNATURE
,
(BOOST_)ASIO_COMPLETION_HANDLER_FOR
, and (BOOST_)ASIO_COMPLETION_TOKEN_FOR
are provided. These macros expand to typename
when concepts
are unsupported.
rebind_executor
to all I/O
object types, as a way to generically rebind them to use alternative I/O
executors. For example:
using my_socket_type = tcp::socket::rebind_executor<my_executor_type>::other;
executor_type
and member function get_executor()
. Note that the presence
of executor_type
and get_executor()
should be
treated as optional, and consequently it may be preferable to access them
via the associated_executor
trait and the get_associated_executor()
helper function.
default_completion_token
trait, so that every I/O
executor type now has an associated default completion token type. This
trait may be used in asynchronous operation declarations as follows:
template < typename IoObject, typename CompletionToken = typename default_completion_token< typename IoObject::executor_type >::type > auto async_xyz( IoObject& io_object, CompletionToken&& token = typename default_completion_token< typename IoObject::executor_type >::type{} );
void
, meaning
no default completion token type is available for the given I/O executor.
default_completion_token
trait for the use_awaitable
completion token, so that it may be used as shown in the following example:
auto socket = use_awaitable.as_default_on(tcp::socket(my_context)); // ... co_await socket.async_connect(my_endpoint); // Defaults to use_awaitable.
socket
object is transformed
from tcp::socket
to have an I/O executor with the default
completion token set to use_awaitable
. Alternatively, the
socket type may be computed directly:
using tcp_socket = use_awaitable_t<>::as_default_on_t<tcp::socket>; tcp_socket socket(my_context); // ... co_await socket.async_connect(my_endpoint); // Defaults to use_awaitable.
async_initiate
to the Windows-specific I/O objects'
asynchronous operations.
basic_socket_acceptor<ip::tcp, my_executor_type>
basic_stream_socket<ip::tcp, my_executor_type>
Protocol
copy and move operations
never throw.
Endpoint
default constructor and move
operations never throw.
noexcept
qualifier to protocol accessors.
noexcept
qualifier to socket move constructors.
case
fall-through
in the free function connect()
implementation.
is_*_buffer_sequence
detection traits for user-defined
sequence types.
CancelIoEx
entry point.
get_option()
member function to be
const.
shutdown
function.
is_dynamic_buffer
.
async_accept
between sockets with different
executor types.
Executor
template
parameter. This template parameter defaults to the asio::executor
type (the polymorphic executor wrapper) but can be used to specify
a user-defined executor type.
asio::io_context&
now accept either an Executor
or a reference to a concrete ExecutionContext
(such
as asio::io_context
or asio::thread_pool
).
io_context
for constructing
another I/O object, as in:
asio::steady_timer my_timer(my_socket.get_executor().context());
asio::steady_timer my_timer(my_socket.get_executor());
io_context
:asio::steady_timer my_timer(my_io_context);
get_io_context
and get_io_service
member functions have now been removed.
async_result
form with an initiate
static member function.
async_result
template now supports a new form:
template <typename CompletionToken, typename Signature> struct async_result { typedef /* ... */ return_type; template <typename Initiation, typename RawCompletionToken, typename... Args> static return_type initiate( Initiation&& initiation, RawCompletionToken&& token, Args&&... args); };
initiate
member function must: (a) transform the
token into a completion handler object handler
; (b)
cause the invocation of the function object initiation
as if by calling std::forward<Initiation>(initiation)(std::move(handler),
std::forward<Args>(args)...)
. Note that the invocation
of initiation
may be deferred (e.g. lazily evaluated),
in which case initiation
and args
must
be decay-copied and moved as required.
async_initiate
has also been
added as a wrapper for the invocation of async_result<>::initiate
.
For backward compatibility, this function supports both the old and
new async_result
forms.
async_initiate
.
handler_type
trait and single-argument
form of async_result
have now been removed.
asio
namespace.
awaitable<>
, co_spawn
, this_coro
,
detached
, and redirect_error
facilities
have been moved from the asio::experimental
namespace
to namespace asio
. As part of this change, the this_coro::token()
awaitable has been superseded by the asio::use_awaitable
completion token.
use_awaitable
and redirect_error
completion tokens work only with asynchronous operations that use
the new form of async_result
with member function initiate
.
Furthermore, when using use_awaitable
, please be aware
that the asynchronous operation is not initiated until co_await
is applied to the awaitable<>
.
DynamicBuffer_v2
concept which is CopyConstructible.
DynamicBuffer_v2
, which supports copy construction.
These new type requirements enable dynamic buffers to be used as
arguments to user-defined composed operations, where the same dynamic
buffer object is used repeatedly for multiple underlying operations.
For example:template <typename DynamicBuffer> void echo_line(tcp::socket& sock, DynamicBuffer buf) { n = asio::read_until(sock, buf, '\n'); asio::write(sock, buf, asio::transfer_exactly(n)); }
DynamicBuffer
type requirements have been
renamed to DynamicBuffer_v1
. These requirements continue
to be compatible with the Networking TS.
is_dynamic_buffer_v1
and is_dynamic_buffer_v2
have been added to test for conformance to DynamicBuffer_v1
and DynamicBuffer_v2
respectively. The existing is_dynamic_buffer
trait has been retained and delegates to is_dynamic_buffer_v1
(unless ASIO_NO_DYNAMIC_BUFFER_V1
is explicitly defined,
in which case it delegates to is_dynamic_buffer_v2
).
dynamic_string_buffer
and dynamic_vector_buffer
classes conform to both DynamicBuffer_v1
and DynamicBuffer_v2
requirements.
ASIO_NO_DYNAMIC_BUFFER_V1
is defined, all support
for DynamicBuffer_v1
types and functions is #ifdef-ed
out. Support for using basic_streambuf
with the read
,
async_read
, read_until
, async_read_until
,
write
, and async_write
functions is also
disabled as a consequence.
async_compose
function that simplifies the implementation
of user-defined asynchronous operations.
make_strand
function, which creates a strand
with a deduced Executor
template argument.
local::basic_endpoint
that takes a
string_view
.
ip::address
,
ip::address_v4
, ip::address_v6
, ip::basic_endpoint
,
and executor_work_guard
classes.
buffer_sequence_begin
and buffer_sequence_end
functions.
ASIO_DISABLE_VISIBILITY
configuration #define
that allows visibility pragmas to be disabled. (Note: If symbols are hidden,
extra care must be taken to ensure that Asio types are not passed across
shared library API boundaries.)
ASIO_STANDALONE
automatically if C++11 or later is detected.
ASIO_ENABLE_BOOST
to explicitly
disable standalone mode when compiling with C++11 or later.
configure
script now defaults to a standalone build
unless Boost is specified or detected.
error::message_size
) occurs on a datagram-oriented
socket.
SO_REUSEPORT
when the reuse_address
option is set.
unistd.h
when targeting Haiku OS, to fix
feature detection.
network_v[46].hpp
headers to the top-level convenience
header.
pthread_cond_timedwait
.
EndpointSequence
iterator type rather than assume the presence of a const_iterator
typedef.
buffer_sequence_begin
and buffer_sequence_end
to prevent implicit conversion. This change addresses an issue where a
call to buffer_sequence_begin
or buffer_sequence_end
could trigger an implicit conversion to const_buffer
or mutable_buffer
.
Whenever this implicit conversion occurred, the return value of buffer_sequence_begin
or buffer_sequence_end
would point to a temporary object.
eof
error on SSL shutdown as it actually indicates
success.
SSL_ERROR_SYSCALL
result without an associated error.
<atomic>
when targeting apple/clang/libc++
with recent Xcode versions, even for C++03. This fixes a warning about
the deprecation of OSMemoryBarrier
.
decltype
support for
that compiler.
_WIN32_WINNT
to 0x0601
(Windows 7).
dispatch
documentation to note that it may call the
supplied function object in the current thread.
post
and defer
documentation to clarify
the the distinction between them.
std::future
availability
with libstdc++.
read_until
.
std::experimental::string_view
and std::string_view
with newer clang/libc++.
std::invoke_result
.
decltype
is available.
size()
, max_size()
or
empty()
on default-constructed resolver results.
std::string_view
detection issue when using clang-cl.
io_context::executor_type::dispatch
.
basic_socket_acceptor::get_option
.
experimental::detached
completion token.
experimental::redirect_error
completion token.
experimental::co_spawn
facility for integration
with the coroutines technical specification.
asio::steady_timer
rather than asio::deadline_timer
.
asio::dynamic_buffer
rather than asio::streambuf
.
asio::io_context::run_for()
function for
blocking clients.
(BOOST_)ASIO_NO_DEPRECATED
is defined.
(BOOST_)ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM
to enable the old Boost.Date_Time interface in basic_socket_streambuf
and basic_socket_iostream
.
is_dynamic_buffer
trait.
async_result
incompatibility with deprecated handler_type
.
basic_resolver_results::value_type
typedef.
SSL_OP_NO_COMPRESSION
is defined.
add_certificate_authority
to process multiple certificates
in a bundle.
std::invoke_result
rather than std::result_of
.
std::string_view
for C++17 or later, and std::experimental::string_view
for C++14. Define the preprocessor macro (BOOST_)ASIO_DISABLE_STD_STRING_VIEW
to force the use of std::experimental::string_view (assuming it is available)
when compiling in C++17 mode.
DynamicBuffer
template arguments are decayed before
using in enable_if
tests.
basic_yield_context
to work with completion signatures
containing reference parameters.
spawn()
correctly
store decayed copies of their function and handler arguments.
basic_socket<Protocol,
SocketService>
we now have simply basic_socket<Protocol>
.
The old interface can be enabled by defining the (BOOST_)ASIO_ENABLE_OLD_SERVICES
macro.
io_context
basis.
ssl::stream<>
constructor argument.
Executor
type requirements and classes to support
an executor framework, including the execution_context
base class, the executor_work
class for tracking outstanding
work, and the executor
polymorphic wrapper. Free functions
dispatch()
, post()
and defer()
have been added and are used to submit function objects to executors.
wrap()
is used to associate
an executor with a handler or other object. The handler hooks for
allocation, invocation and continuation have been deprecated.
system_executor
class has been added as a default
executor.
io_service
class is now derived from execution_context
and implements the executor type requirements in its nested executor_type
class. The member functions dispatch()
, post()
,
defer()
and wrap()
have been deprecated.
The io_service::work
class has been deprecated.
io_service
member function reset()
has been renamed to restart()
. The old name is retained
for backward compatibility but has been deprecated.
make_service<>()
function is now used to add
a new service to an execution context such as an io_service
.
The add_service()
function has been deprecated.
strand<>
template has been added to allow
strand functionality to be used with generic executor types.
io_service
via a context()
member
function. The get_io_service()
member function is deprecated.
io_service::post()
,
io_service::dispatch()
, io_service::strand::post()
and io_service::strand::dispatch()
functions still require
copyable handlers.
expiry()
member function for obtaining the expiry
time. The accessors expires_at()
and expires_after()
have been deprecated, though those names are retained for the mutating
members.
std::packaged_task
class template is now supported
as a completion handler. The initiating operation automatically returns
the future associated with the task. The package()
function
has been added as a convenient factory for packaged tasks.
wait()
and async_wait()
operations that may be used to wait
for readiness. The null_buffers
type has been deprecated.
address_cast<>()
,
make_address()
, make_address_v4()
and
make_address_v6()
free functions. The from_string()
,
to_v4()
, to_v6()
and v4_mapped()
member functions have been deprecated.
ip::address
now represents an
invalid address value that is neither IPv4 nor IPv6.
buffer()
overloads that generate mutable buffers
for non-const string
objects.
asio::streambuf
class.
This support includes:
dynamic_string_buffer
and dynamic_vector_buffer
adapter classes that meet the DynamicBufferSequence
type requirements.
dynamic_buffer()
factory functions for creating
a dynamic buffer adapter for a vector
or string
.
read()
, async_read()
,
write()
and async_write()
, read_until()
and async_read_until()
free functions that directly
support dynamic buffer sequences.
address_iterator_v4
for iterating across IPv4
addresses
address_iterator_v6
for iterating across IPv6
addresses
address_range_v4
to represent a range of IPv4
addresses
address_range_v6
to represent a range of IPv6
addresses
network_v4
for manipulating IPv4 CIDR addresses,
e.g. 1.2.3.0/24
network_v6
for manipulating IPv6 CIDR addresses,
e.g. ffe0:/120
<asio/ts/*.hpp>
that correspond to the headers in the proposal.
thread_pool
class.
spawn()
to be executor-aware.
spawn()
overload that takes only a function object.
spawn()
and yield_context
to permit nested
calls to the completion handler.
std::endl
to ensure output is
flushed.
ssl::stream<>
bug that may result in spurious
'short read' errors.
ssl::stream<>
constructor argument.
yield_context
object with asynchronous operations.
ConnectEx
function are
mapped to their portable equivalents.
join_group
failures
as non-fatal.
kqueue
reactor so that it works on FreeBSD.
kqueue
reactor which resulted
in spinning when using serial ports on Mac OS.
kqueue
reactor support for read-only file descriptors.
/dev/poll
reactor.
WSASocketW
, as WSASocketA
has been deprecated.
use_future
and spawn()
are not made available when including the asio.hpp
convenience
header.
asio::strand
as deprecated. Use asio::io_service::strand
instead.
kqueue
backend that was introduced
in Asio 1.10.2.
gcc
on AIX.
gcc
problem to do with anonymous enums.
HANDLE
backend change to ignore ERROR_MORE_DATA
.
Instead, the error will be propagated as with any other (i.e. in an error_code
or thrown as a system_error
), and the number of bytes transferred
will be returned. For code that needs to handle partial messages, the
error_code
overload should be used.
signal_set
implementation's
signal number check.
SO_UPDATE_CONNECT_CONTEXT
is defined.
VerifyVersionInfo
rather than GetVersionEx
, as GetVersionEx
has
been deprecated.
asio::spawn()
to work correctly with new Boost.Coroutine
interface.
asio::spawn()
coroutines are correctly
unwound when cleaned up by the io_service
destructor.
io_service::wrap()
and strand::wrap()
.
ConnectEx
,
if available, for connection-oriented IP sockets.
io_service
backend for non-Windows (and non-IOCP
Windows) platforms to use a single condition variable per io_service
instance. This addresses a potential race condition when run_one()
is used from multiple threads.
boost::chrono
and std::chrono
clocks.
EV_CLEAR
handling in the kqueue backend,
to address other cases where the close()
system call may hang
on Mac OS X.
resolver_query_base::flags::operator~
.
select
reactor more efficient on Windows for large
numbers of sockets.
gcc
.
GetQueuedCompletionStatus
timeout workaround
on recent versions of Windows.
FormatMessageW
rather than FormatMessageA
, as the Windows store does not
permit the latter.
io_service
, strand
,
buffers, composed operations, timers, etc., should all work as normal.
cancel()
function is not supported for sockets.
Asynchronous operations may only be cancelled by closing the socket.
null_buffers
are not supported.
tcp::no_delay
and socket_base::keep_alive
options are supported.
ASIO_STANDALONE
on your compiler command
line or as part of the project options. This standalone configuration has
been tested for the following platforms and compilers:
-std=c++11
)
-std=c++11 -stdlib=libc++
)
async_connect
were not correctly propagated through to
the completion handler.
io_service
. When the
bug occurs, the result of an asynchronous operation (error and bytes tranferred)
is incorrectly discarded and zero values used instead. For TCP sockets
this results in spurious end-of-file notifications.
async_wait
on a signal that is already raised.
async_write_at
operations.
HANDLE
backend to treat ERROR_MORE_DATA
as a non-fatal error when returned by GetOverlappedResult
for a synchronous read.
generic
as a keyword. Added
a workaround that renames the namespace to cpp_generic
when
those language extensions are in effect.
async_result
support in 1.10.0. In particular, the buffered stream templates have been
updated so that they adhere to current handler patterns.
use_future
support for Microsoft Visual Studio 2012.
std::min
in the Windows IOCP backend to avoid
a dependency on the <algorithm>
header.
SSL_CTX_clear_options
function.
handler_type
and async_result
,
that allow the customisation of the return type of an initiating function.
asio::spawn()
function, a high-level wrapper for
running stackful coroutines, based on the Boost.Coroutine library. The
spawn()
function enables programs to implement asynchronous
logic in a synchronous manner. For example: size_t n = my_socket.async_read_some(my_buffer,
yield);
. For further information, see Stackful
Coroutines.
asio::use_future
special value, which provides first-class
support for returning a C++11 std::future
from an asynchronous
operation's initiating function. For example: future<size_t>
= my_socket.async_read_some(my_buffer, asio::use_future);
. For further
information, see C++ 2011
Support - Futures.
asio_handler_is_continuation
.
Asynchronous operations may represent a continuation of the asynchronous
control flow associated with the current executing handler. The asio_handler_is_continuation
hook can be customised to return true
if this is the case,
and Asio's implementation can use this knowledge to optimise scheduling
of the new handler. To cover common cases, Asio customises the hook for
strands, spawn()
and composed asynchronous operations.
generic::datagram_protocol
,
generic::raw_protocol
, generic::seq_packet_protocol
and generic::stream_protocol
, which implement the Protocol
type requirements, but allow the user to specify the address family (e.g.
AF_INET
) and protocol type (e.g. IPPROTO_TCP
)
at runtime. For further information, see Support
for Other Protocols.
ip::tcp::socket
can be converted into a generic::stream_protocol::socket
via
move construction. For further information, see Support
for Other Protocols.
basic_socket_acceptor<>
's accept()
and async_accept()
functions to allow a new connection to
be accepted directly into a socket of a more generic type. For example,
an ip::tcp::acceptor
can be used to accept into a generic::stream_protocol::socket
object. For further information, see Support
for Other Protocols.
ASIO_STANDALONE
on your compiler command line or as part of the project options. This standalone
configuration has currently been tested for the following platforms and
compilers:
-std=c++11
)
-std=c++11 -stdlib=libc++
)
ssl::stream<>
class's handshake()
and async_handshake()
functions have been added. These accept a ConstBufferSequence
to be used as initial input to the ssl engine for the handshake procedure.
ssl::context
objects.
set_verify_depth()
function to the ssl::context
and ssl::stream<>
classes.
add_certificate_authority()
,
use_certificate()
, use_certificate_chain()
,
use_private_key()
, use_rsa_private_key()
and use_tmp_dh()
, have been added to the ssl::context
class.
ssl::context
to automatically disable SSL compression
by default. To enable, use the new ssl::context::clear_options()
function, as in my_context.clear_options(ssl::context::no_compression)
.
signal_set
implementation.
#warning
directive.
epoll
implementation.
error_code
with an invalid (i.e. NULL
) error_category
.
basic_waitable_timer
's underlying implementation so
that it can handle any time_point
value without overflowing
the intermediate duration objects.
run()
and poll()
on the same io_service
object.
ssl::rfc2818_verification
class.
asio/detail/winsock_init.hpp
for details.
basic_socket::get_option
's
documentation.
long
rather than int
for SSL_CTX
options, to match OpenSSL.
_snwprintf
to address a compile error due to
the changed swprintf
signature in recent versions of MinGW.
io_service
threads due to running out of work.
accept
as non-fatal.
ip::tcp::iostream
and C++11.
#include <cctype>
, needed for some versions
of MinGW.
gcc
's atomic builtins on ARM CPUs, when
available.
io_service
has been destroyed.
epoll_create1()
function but always fail with ENOSYS.
buffered_write_stream
.
epoll_reactor
backend to do lazy registration
for EPOLLOUT
events.
epoll_reactor
handling of out-of-band data, which
was broken by an incomplete fix in the last release.
OPENSSL_NO_ENGINE
feature test #define
.
windows::object_handle
so that it works with Windows
compilers that support C++11 move semantics (such as g++
).
g++
4.7 when compiling in C++11 mode.
signal_set
handlers were not being delivered
when the io_service
was constructed with a concurrency_hint
of 1.
basic_waitable_timer
based around
the C++11 clock type requirements. It may be used with the clocks from
the C++11 <chrono>
library facility or, if those are
not available, Boost.Chrono. The typedefs high_resolution_timer
,
steady_timer
and system_timer
may be used to
create timer objects for the standard clock types.
windows::object_handle
class for performing waits
on Windows kernel objects. Thanks go to Boris Schaeling for contributing
substantially to the development of this feature.
connect()
can return EAGAIN in certain circumstances.
Remapped this to another error so that it doesn't look like a non-blocking
operation.
buffered_write_stream
.
io_service
is repeatedly run without anything to do.
concurrency_hint
is 1) to eliminate a lock/unlock
pair.
epoll_reactor
speculative operations to
be performed without holding the lock.
epoll_reactor
's
I/O operation immediately before the corresponding handler is called.
This also improves scalability across CPUs when multiple threads
are running the io_service
.
boost::array
or std::array
)
of exactly two buffers.
async_read_until
.
signal()
function from the global namespace.
deadline_timer
implementation so that it does
not read the clock unless the timer heap is non-empty.
null_buffers
operations
so that they obey the user's non-blocking setting.
fd_set
at runtime when
using Windows.
epoll_reactor
initialisation.
(BOOST_)ASIO_STRAND_IMPLEMENTATIONS
to the desired number.
(BOOST_)ASIO_ENABLE_SEQUENTIAL_STRAND_ALLOCATION
flag which switches the allocation of strand implementations to use a round-robin
approach rather than hashing.
strand.post()
is used.
-std=c++0x
mode on g++ 4.5 or higher.
signal()
or sigaction()
.
errno
is preserved across the implementation's
signal handler.
io_service
destructor).
OPENSSL_NO_SSL2
is defined.
tick_count_timer
example by making
the duration type signed. Previously, a wait on an already-passed deadline
would not return for a very long time.
(BOOST_)ASIO_ENABLE_OLD_SSL
.
asio::buffer()
overloads for std::array
,
when available. The support is automatically enabled when compiling in
-std=c++0x
mode on g++ 4.3 or higher, or when using
MSVC 10. The support may be explicitly enabled by defining (BOOST_)ASIO_HAS_STD_ARRAY
,
or disabled by defining (BOOST_)ASIO_DISABLE_STD_ARRAY
.
array
,
shared_ptr
, weak_ptr
and atomic
when they are available, rather than the Boost equivalents.
std::error_code
and std::system_error
is no longer enabled by default for g++ 4.5, as that compiler's standard
library does not implement std::system_error::what()
correctly.
fork()
system call. Programs that use
fork()
must call io_service.notify_fork()
at
the appropriate times. Two new examples have been added showing how to
use this feature.
close()
system call. In particular, assume that most operating systems won't have
close()
fail with EWOULDBLOCK
, but if it does
then set the blocking mode and restart the call. If any other error occurs,
assume the descriptor is closed.
EV_ONESHOT
seems to cause problems on some
versions of Mac OS X, with the io_service
destructor getting
stuck inside the close()
system call. Changed the kqueue backend
to use EV_CLEAR
instead.
what()
messages.
shutdown_service()
member functions to be private.
signal_set_service::cancel()
.
SignalHandler
example.
signal_set_service.hpp
so that constants like NSIG
may be used.
signal_set_service
implementation so that it doesn't
assume that SIGRTMAX
is a compile-time constant.
signal_set
.
Programs may add one or more signals to the set, and then perform an async_wait()
operation. The specified handler will be called when one of the signals
occurs. The same signal number may registered with multiple signal_set
objects, however the signal number must be used only with Asio.
(BOOST_)ASIO_ENABLE_HANDLER_TRACKING
, Asio writes debugging
output to the standard error stream. The output records asynchronous operations
and the relationships between their handlers. It may be post-processed
using the included handlerviz.pl
tool to create a visual
representation of the handlers (requires GraphViz).
asio::streambuf
where the consume()
function did not always update the internal buffer pointers correctly.
The problem may occur when the asio::streambuf
is filled with
data using the standard C++ member functions such as sputn()
.
(Note: the problem does not manifest when the streambuf is populated by
the Asio free functions read()
, async_read()
,
read_until()
or async_read_until()
.)
perform()
function are not correctly
re-registered with kqueue.
std::error_code
and std::system_error
is no longer enabled by default for MSVC10, as that compiler's standard
library does not implement std::system_error::what()
correctly.
buffers_iterator<>
and ip::basic_resolver_iterator
classes so that the value_type typedefs are non-const byte types.
ip::tcp::iostream
.
A timeout is set by calling expires_at()
or expires_from_now()
to establish a deadline. Any socket operations which occur past the deadline
will put the iostream into a bad state.
error()
member function to socket iostreams, for
retrieving the error code from the most recent system call.
basic_deadline_timer::cancel_one()
function. This
function lets you cancel a single waiting handler on a timer. Handlers
are cancelled in FIFO order.
transfer_exactly()
completion condition. This
can be used to send or receive a specified number of bytes even if the
total size of the buffer (or buffer sequence) is larger.
connect()
and async_connect()
.
These operations try each endpoint in a list until the socket is successfully
connected.
buffer_size()
function so that it works for buffer
sequences in addition to individual buffers.
buffer_copy()
function that can be used to copy
the raw bytes between individual buffers and buffer sequences.
read()
, read_at()
,
write()
and write_at()
that do not require a
completion condition.
static_assert
is also used to generate an informative error message. This checking may
be disabled by defining (BOOST_)ASIO_DISABLE_HANDLER_TYPE_REQUIREMENTS
.
std::error_code
and std::system_error
,
when available. The support is automatically enabled when compiling in
-std=c++0x
mode on g++ 4.5 or higher, or when using
MSVC 10. The support may be explicitly enabled by defining ASIO_HAS_STD_SYSTEM_ERROR
,
or disabled by defining ASIO_DISABLE_STD_SYSTEM_ERROR
. (Available
in non-Boost version of Asio only.)
is_loopback()
, is_unspecified()
and
is_multicast()
functions consistently available across the
ip::address
, ip::address_v4
and ip::address_v6
classes.
non_blocking()
functions for managing the non-blocking
behaviour of a socket or descriptor. The io_control()
commands
named non_blocking_io
are now deprecated in favour of these
new functions.
native_non_blocking()
functions for managing the
non-blocking mode of the underlying socket or descriptor. These functions
are intended to allow the encapsulation of arbitrary non-blocking system
calls as asynchronous operations, in a way that is transparent to the user
of the socket object. The functions have no effect on the behaviour of
the synchronous operations of the socket or descriptor.
io_control()
member function for socket acceptors.
native_type
typedefs in favour of native_handle_type
, and the native()
member functions in favour of native_handle()
.
release()
member function to posix descriptors. This
function releases ownership of the underlying native descriptor to the
caller.
SOCK_SEQPACKET
).
io_service::stopped()
function that can be used
to determine whether the io_service
has stopped (i.e. a reset()
call is needed prior to any further calls to run()
, run_one()
,
poll()
or poll_one()
).
-std=c++0x
mode on g++ 4.5 or higher, or when using MSVC10.
ip::basic_endpoint<>
objects (such
as ip::tcp::endpoint
and ip::udp::endpoint
).
assign()
may have been dup()
-ed,
and so require explicit deregistration from the reactor.
io_service()
.
The get_io_service()
member functions should be used instead.
resolver_query
and resolver_iterator
from the ip::tcp
, ip::udp
and ip::icmp
classes.
FIONBIO
constant to int to suppress
a compiler warning on some platforms.
-Wshadow
compiler option.
ip::address_v4::broadcast()
is used on 64-bit platforms.
timerfd
support) that prevents timely delivery of deadline_timer
handlers,
after the program has been running for some time.
deadline_timer
may never fire if the io_service
is running in a background
thread.
has_service<>
from compiling.
close()
/closesocket()
failures are correctly
propagated.
InitializeCriticalSectionAndSpinCount
.
pselect()
on HP-UX, if it is available.
deadline_timer
objects
with expiry times set more than 5 minutes in the future may never expire.
0
, as per the documentation.
const_buffers_1
.
Protocol
and id
to avoid clashing with
Objective-C++ keywords.
vector
reallocation performance issue that can occur
when there are many active deadline_timer
objects.
io_control()
implementation on 64-bit Mac
OS X and BSD platforms.
accept()
are incorrectly treated as successes.
asio/impl/src.cpp
in favour of asio/impl/src.hpp
.
#include
s, e.g. if the program uses boost::array but does
not explicitly include <boost/array.hpp>
.)
deadline_timer
implementation to improve performance.
asio::streambuf
with async_read()
and async_read_until()
. These read operations now use the
existing capacity of the streambuf
when reading, rather than
limiting the read to 512 bytes.
asio/impl/src.cpp
in one source file in a program, then build the program with (BOOST_)ASIO_SEPARATE_COMPILATION
defined in the project/compiler settings. Alternatively, (BOOST_)ASIO_DYN_LINK
may be defined to build a separately-compiled Asio as part of a shared
library.
(BOOST_)ASIO_DISABLE_FENCED_BLOCK
to permit
the disabling of memory fences around completion handlers, even if thread
support is enabled.
null_buffers
variant of
async_send_to
.
isdigit
in getaddrinfo
emulation.
buffers_iterator
.
null_buffers
operations on Windows.
timerfd
for dispatching timers on Linux, when
available.
ip::resolver_query_base::flags
as per
the TR2 proposal. This type prevents implicit conversion from int
to flags
, allowing the compiler to catch cases where users
incorrectly pass a numeric port number as the service name.
#define NOMINMAX
for all Windows compilers. Users can
define (BOOST_)ASIO_NO_NOMINMAX
to suppress this definition.
error::eof
result to the completion handler.
io_control()
member functions to always call
ioctl
on the underlying descriptor when modifying blocking
mode.
InternetProtocol::resolver_query
and InternetProtocol::resolver_iterator
,
as neither typedef is part of the documented InternetProtocol
requirements. The corresponding typedefs in the ip::tcp
,
ip::udp
and ip::icmp
classes have been deprecated.
select()
.
(BOOST_)ASIO_DISABLE_THREADS
macro that allows Asio's
threading support to be independently disabled.
boost::addressof
to get the address of handler objects, rather than applying operator&
directly.
OVERLAPPED
structure to be valid until both the initiating
function call has returned and the completion packet has been delivered.
boost_
prefix to the extern "C"
thread entry point function.
getaddrinfo
emulation, only check the socket type (SOCK_STREAM
or SOCK_DGRAM
) if a service name has been specified. This
should allow the emulation to work with raw sockets.
buffered*_stream<>
templates to treat 0-byte
reads and writes as no-ops, to comply with the documented type requirements
for SyncReadStream
, AsyncReadStream
, SyncWriteStream
and AsyncWriteStream
.
throw
keyword to boost::throw_exception()
to allow Asio to be used when exception support is disabled. Note that
the SSL wrappers still require exception support.
HANDLE
fails.
_GLIBCXX_DEBUG
is defined.
(BOOST_)ASIO_HASH_MAP_BUCKETS
may be used to tweak the sizes used for the bucket arrays. (N.B. this feature
introduced a bug which was fixed in Asio 1.4.3 / Boost 1.40.)
io_control()
so that it adheres
to the documented type requirements for IoControlCommand.
ReadFile
call fails with ERROR_MORE_DATA
. This enables a hack where
a windows::stream_handle
can be used with a message-oriented
named pipe.
(BOOST_)ASIO_DISABLE_SERIAL_PORT
is defined.
windows::overlapped_ptr::complete()
are
correctly passed to the completion handler.
size_t CompletionCondition(error_code
ec, size_t total)
, where the return value indicates the maximum
number of bytes to be transferred on the next read or write operation.
(The old CompletionCondition signature is still supported for backwards
compatibility).
windows::overlapped_ptr
class to allow arbitrary overlapped
I/O functions (such as TransmitFile
) to be used with Asio.
eventfd
descriptor is now
used (rather than a pipe) to interrupt a blocked select/epoll reactor.
lowest_layer()
.
io_service
implementations now use lazy initialisation
to reduce the memory usage of an io_service
object used only
as a message queue.
HANDLE
s such as
named pipes (requires HANDLE
s that work with I/O completion
ports).
HANDLE
s such as files
(requires HANDLE
s that work with I/O completion ports).
null_buffers
type.
read_until()
and async_read_until()
overloads that take a user-defined function object for locating message
boundaries.
(BOOST_)ASIO_ENABLE_TWO_LOCK_QUEUE
)
that may provide better io_service
scalability across many
processors.
First stable release of Asio.